Move EmailAddress & UserRedirect into models/user/ (#17607)

* Move EmailAddress into models/user/

* Fix test

* rename user_mail to user_email

* Fix test

* Move UserRedirect into models/user/

* Fix lint & test

* Fix lint

* Fix lint

* remove nolint comment

* Fix lint

models/user/redirect_test.go

@@ -0,0 +1,23 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package user
+
+import (
+	"testing"
+
+	"code.gitea.io/gitea/models/db"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLookupUserRedirect(t *testing.T) {
+	assert.NoError(t, db.PrepareTestDatabase())
+
+	userID, err := LookupUserRedirect("olduser1")
+	assert.NoError(t, err)
+	assert.EqualValues(t, 1, userID)
+
+	_, err = LookupUserRedirect("doesnotexist")
+	assert.True(t, IsErrUserRedirectNotExist(err))
+}